A pipe having disposable protective means thereon and method of making same

ABSTRACT

A pipe having a resilient disposable protective ring on one end thereof, wherein the ring is utilized during manufacture of the pipe for forming an annular groove at one end of the pipe for receiving an O-ring therein when the pipe is installed to another pipe, said ring being left in place after the pipe is manufactured to prevent breakage of the pipe during storage and handling of the pipe, and said ring being removed and thrown away when the pipe is to be installed to another pipe.

3,724,506 1 51 Apr.3,1973

[54] PIPE HAVING DISPOSABLE 25/39 ......25/39 11/1971 Peck ct 12/1963Gannaway 9/1967 Hesselholt...

PROTECTIVE MEANS THEREON AND METHOD OF MAKING SAME [76] Inventor: LarryG. Crowe, 1020 3rd Avenue, 1 Pri ar E minr William R, Cline N.E.,Waverly, Iowa 50677 Feb. 22, 1971 Attorney-Zarley, McKee & ThomteABSTRACT [22] Filed:

thrown away when the another pipe.

[56] References Cited UNITED STATES PATENTS pipe is to be installed to 71952 whitin .264/228 X 3 Claims, 6 Drawing Figures PATENTEUAPR 3 I975sum 1 OF 2 FIG.

INVENTOR LARRY G. CROWE BY m ma ATTORNEYS PATENTEDAPRB 1m I 3,724,506sumaur2 INVENTOR LARRY G. CROWE ATTORNEYS PIPE HAVING DISPOSABLEPROTECTIVE MEANS THEREON AND METHOD OF MAKING SAME BACKGROUND OF THEINVENTION This invention relates to a concrete pipe and to the method ofmaking same, and more particularly, to a disposable protective ring onone end of the pipe for preventing damage to the pipe during handlingand storage.

In the prior art, a concrete pipe is commonly manufactured with a bellor socket end and with a male or spigot end. This concrete pipegenerally has a relatively thin wall and during handling and storage,the pipe is easily broken or damaged such as, for example, when it isstruck by another pipe. In some instances, there is up to a 25 percentrejection rate of the pipes due to breakage and the like. This highrejection rate is both expensive and wasteful and in fact, the cost ofdisposing of the broken pipe often equals the cost of a new pipe. Theproblem is particularly acute at the male or spigot end of the pipe,which has a thinner wall than the socket or bell end of the pipe. Such apipe is commonly manufactured in a Packerhead machine which includes amold structure for forming the pipe and a cap of metal or the like forforming the male or spigot end of the pipe.

Typically, a plant set up for manufacturing the pipe would use aneoprene rubber insert in a cast iron retaining ring to form an O-ringgroove in the spigot end of the pipe and such plant would normally havea quantity of 50 or more castiron rings with inserts for each size ofpipe to be manufactured. Approximately 600 pieces of pipe having a 4foot length and an 8 inch diameter, for example, can be manufacturedduring one 8-hour shift; and it is, therefore, necessary to strip theretaining ring from the pipe while it is still green so that theretaining ring may be reused on other pipes. When the cast iron ring ispulled off the pipe, the neoprene strip or insert springs loose andoften spalls the edges of the O-ring groove. Moreover, when the pipe isstacked in a storage area or handled for storage or shipment, the spigotend of the broken.

Other manufacturers use a steel snap ring to form the O-ring groove inthe spigot endof the pipe, and this snap ring is removed from the pipeas soon as the pipe is manufactured so that the snap ring may be used inmanufacturing other pipes. Accordingly, the pipes are likely to bedamaged during handling and storage.

The present invention provides a means for forming pipe is frequently anO-ring groove in a spigot end of the pipe which is not removedimmediately upon manufacture of the pipe and which is left in placeduring handling and storage of the pipe and is removed only when thepipe is to be installed to another pipe, said means comprising aresilient, disposable protective ring which forms the O- ring grooveduring manufacture of the pipe and which is left on the pipe duringcuring thereof and which protects the spigot end of the pipe duringhandling and storage to prevent breakage of the pipe.

OBJECTS OF THE INVENTION It is an object of this invention to provide apipe having protective means thereon and a method of making same.

It is a further object of this invention to provide a means for formingan O-ring groove in a spigot end of a pipe, which means is left in placeon the pipe once the pipe is manufactured to protect the spigot end ofthe pipe during handling and storage.

Another object of this invention is to provide a resilient, disposableprotective ring used to form an O- ring grove in the spigot end of aconcrete pipe and which is left in place when the pipe is manufacturedto protect the spigot end of the pipe during handling and storage, saidring being removed and thrown away when the pipe is installed to anotherpipe.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a part sectional view inelevation of a portion of an apparatus for manufacturing the pipe andshowing the means for forming the spigot end of the pipe.

FIG. 2 is an exploded perspective view of a pipe showing the means forforming the spigot end thereof at one end of the pipe.

FIG. 3 is a top perspective view of a portion of the apparatus forforming the spigot end of the pipe.

FIG. 4 is a top perspective view of another portion of the apparatus forforming the spigot end of the pipe.

FIG. 5 is a top perspective view of still another portion of theapparatus for forming the spigot end of the pipe.

FIG. 6 is a top perspective view of a plurality of concrete pipes instacked relationship showing the manner in which the resilientdisposable protective ring serves as a bufier between adjacent pipes toprevent breakage of the spigot ends thereof.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings,wherein like reference numerals refer to like parts throughout theseveral views, a pipe P constructed in accordance with the presentinvention is shown in section in FIG. 1 encased in a portion of an,apparatus for manufacturing the pipe.

The pipe P is an elongate cylindrical member having a hell or socket end1 and a male or spigot end 2. The bell end 1 is of conventionalconstruction and includes an enlarged diameter inside portion 3 and anenlarged outside diameter portion 4.

The spigot end 2 of the pipe has a thickened portion 5, the outersurface 6 of which is tapered inwardly toward the end thereof to aid inassembling the spigot end 2 of the pipe into a bell end of an adjacentpipe.

The apparatus for manufacturing the pipe P includes a socke curingpallet and bell-down unit indicated schematically at 7 and disposed inpartially surrounding relationship to the bell end 1 of the pipe with aportion of the socket curing pallet and bell-down unit 7 extended,inside the end 1 of the pipe P.

A cylindrical jacket mold 8 is arranged in surrounding relationship tothe pipe P and determines the configuration and size of the pipe whenconcrete is poured thereinto in forming the pipe.

A cap for forming the spigot end of the pipe is indicated generally at 9and is positioned at the upper end of jacket mold 8, as viewed in FIG.1, and has a predetermined size and configuration in relation to thesize and configuration of jacket mold 8 to give a selected size andconfiguration of the spigot end 2 of the pipe P. The cap 9 comprises atwo-piece steel retaining ring 10 consisting of two semi-circular parts11 and 12 (FIG. 4). The two parts 11 and 12 of the twopiece steelretaining ring 10, each include a thickened base portion 13 having anoutwardly flared tapered surface 14 and a relatively narrow or thinaxially upstanding wall or flange l5 thereon at the outer marginal edgeof the thickened portion 13 and extending axially from the upper end ofthe tapered portion 14. The annular flange 15 and thickened portion 13define an annular, axially facing shoulder 16 and annular, radiallyinwardly facing wall or surface 17.

A one-piece cast iron ring 18 has a thickened portion 19 with a radiallyinwardly facing tapered surface 20 and an axially depending annular wallor flange 21 extending downwardly from the outer marginal edge ofthickened portion 19. The one-piece cast iron ring 18 is adapted to bedisposed with the outer surface of flange 21 and thickened portion 19disposed in mating abutting relationship with the surface 17 on flange15 of two-piece retaining ring 10, and the lower edge of flange 21 inmating abutting relationship with shoulder 16 on thickened portion 13 oftwo-piece retaining ring 10. The flange 21 and thickened portion 19 ofcast iron ring 18 define an axially downwardly facing shoulder 22 and aradially inwardly facing surface or wall 23. The thickness of flange 21is only approximately onehalf as great as the width of shoulder 16 andthus when the flange 21 is positioned against surface 17 and shoulder16, a portion 24 of shoulder 16 is exposed. The shoulder 22, surface 23and portion 24 of shoulder 16 define a generally rectangularly shapedrecess 25.

A one-piece annular resilient disposable protective ring 26 of neoprene,polystyrene, or the like, having generally rectangular outercircumferential surface 27 is adapted to be clamped in recess 25,between shoulders 22 and. 24 with the outer surface 27 in abuttingrelationship with surface 23 on flange 21 of cast iron ring 18.

The ring 26 has a thickness dimension greater than the depth of recessand a portion 28 thereof accordingly projects radially inwardly beyondtapered surface 20 of ring 18.

A generally washer-shaped, one-piece steel locking ring 29 having aninside diameter slightly greater than the outside diameter of flange l5and less than the maximum diameter of tapered surface 14 is adapted tobe disposed in surrounding relationship to the two-piece steel retainingring 10 for holding the retaining ring 10, cast iron ring 18 anddisposable protective ring 26 in assembled relationship, the insidediameter of locking ring 29 engaging the tapered surface 14 of two-pieceretaining ring 10 to securely wedge the portions together.

A rotatable and reciprocable packershaft 30 is disposed co-axiallywithin jacket mold 8 and includes a roller head or packerhead 31, theouter diameter of which is spaced radially inwardly of the innerdiameter ofjacket mold 8 a predetermined amount to determine thethickness of the wall of pipe P.

In use, the jacket mold 8 is brought into operative relationship withthe socket curing pallet and belldown unit 7 as shown in FIG. 1. Thepackershaft 30 is disposed adjacent the bottom of jacket mold 8 inproximity to the socket curing pallet and bell-down" unit 7. Concrete isthen poured into the mold, filling the space between the bell-down unit7 and the inside surface of jacket mold 8. The packershaft 30 andbelldown unit are slowly rotated, and the packershaft is simultaneouslydrawn upwardly through the jacket mold 8 as concrete is added thereto.Concrete is added to the mold and the packershaft drawn upwardly untilthe spigot end of the pipe is completed. The disposable protective ring26 forms an O-ring groove 32 in the outer surface of the spigot end ofthe pipe. The pipe is subsequently removed from the mold for curing andthe cap 9 is removed from the spigot end thereof. The steel locking ring29 is first removed axially from around the two-piece retaining ring 10which may then be simply separated and removed from around the onepiececast iron ring 18 which is then slipped axially off the end 2 of thepipe; The resilient disposable protective ring 26 is left in position inthe O-ring groove 32 on the spigot end of the pipe and serves as abumper or buffer for preventing breakage of the spigot end'of the pipedue to impact on the pipe during handling and storage.

FIG. 6 depicts a plurality of pipes P in stacked relationship andillustrates the manner in which the protective rings 26 prevent directcontact between spigot ends of adjacent pipes thereby precluding thepossibility of breakage of the pipes P due t impact therebetween.

When the pipe is to be assembled to another pipe, the disposableprotective ring 26 is removed and a suitable rubber O-ring or the likeplaced in the groove and the pipe then assembled to an adjacent pipe.

While the pipe has been described as manufactured with a bell-downsystem, it could equally as well be manufactured with a bell-up" system.The specific manner of manufacture of pipe is not critical, theimportant point being the disposable protective ring 26 which is used toform the O-ring groove in the spigot end of the pipe and which serves asa bumper or buffer for protecting the pipe during handling and storageand is then removed and thrown away when the pipe is assembled toanother pipe.

Accordingly, with the present invention, the high rejection rate ofconcrete pipe due to breakage and the like is substantially eliminated,thus reducing the cost of manufacturing the pipe and resulting in aneventual saving to the consumer.

While specific materials have been described for the various portions ofthe cap, other suitable materials could equally as well be used; andwhile the present invention is primarily intended for manufacturingpipes having a diameter of 4 inches to 15 inches and a length of from 2feet to l2 feet, it could obviously be used in manufacturing pipeshaving different sizes.

As this invention may be embodied in several forms without departingfrom the spirit or essential characteristics thereof, the presentembodiment is therefore illustrative and not restrictive, since thescope of the invention is defined by the appended claims rather than bythe description preceding them, and all changes that fall within themetes and bounds of the claims or that form their functional as well asconjointly cooperative equivalents, are therefore intended to beembraced by those claims.

I claim:

1. A tubular pipe having an annular groove formed in its outercircumference adjacent at least one end thereof, a disposable protectivemeans on said pipe comprising a disposable annular resilient means insaid annular groove, said resilient means being positioned on said pipeduring the manufacture thereof to create said annular groove, saiddisposable resilient means having an exposed outer surface forprotecting the pipe against breakage during handling and storage, saiddisposable resilient means being readily removable from the pipe topermit the installation of an O-ring in said groove when it is desiredto assemble the pipe to another pipe, the outer circumference of saidpipe being substantially equal adjacent both sides of said annulargroove so that said exposed outer surface of said resilient means ispositioned outwardly of the said outer circumference of said pipe forengagement with other pipes when a plurality of pipes are stacked toprevent pipe to pipe contact.

2. A method of making a pipe having disposable protective means thereoncomprising, providing a mold, putting concrete in said mold, operating aportion of said mold to form arpipe therein as concrete is put into saidmold, providing an annular removable cap means at one end of said moldfor forming one end of said pipe, providing a resilient means in saidcap means having a portion thereof projecting radially inwardly intosaid concrete to form an annular groove in said one end of said pipe andhaving a portion thereof projecting radially outwardly from saidconcrete, removing said pipe from said mold, removing said removable capmeans from said one end of said pipe and leaving said resilient means insaid annular groove in said one end of said pipe to provide aprotective: means for said pipe during the handling and storage thereof.

3. The method of making a tubular pipe as in claim 2 wherein saidannular ring is removed from said groove in said pipe prior to'assemblyof said pipe to another pipe to permit an O-ring to be installed in saidgroove.

1. A tubular pipe having an annular groove formed in its outercircumference adjacent at least one end thereof, a disposable protectivemeans on said pipe comprising a disposable annular resilient means insaid annular groove, said resilient means being positioned on said pipeduring the manufacture thereof to create said annular groove, saiddisposable resilient means having an exposed outer surface forprotecting the pipe against breakage during handling and storage, saiddisposable resilient means being readily removable from the pipe topermit the installation of an O-ring in said groove when it is desiredto assemble the pipe to another pipe, the outer circumference of saidpipe being substantially equal adjacent both sides of said annulargroove so that said exposed outer surface of said resilient means ispositioned outwardly of the said outer circumference of said pipe forengagement with other pipes when a plurality of pipes are stacked toprevent pipe to pipe contact.
 2. A method of making a pipe havingdisposable protective means thereon comprising, providing a mold,putting concrete in said mold, operating a portion of said mold to forma pipe therein as concrete is put into said mold, providing an annularremovable cap means at one end of said mold for forming one end of saidpipe, providing a resilient means in said cap means having a portionthereof projecting radially inwardly into said concrete to form anannular groove in said one end of said pipe and having a portion thereofprojecting radially outwardly from said concrete, removing said pipefrom said mold, removing said removable cap means from said one end ofsaid pipe and leaving said resilient means in said annular groove insaid one end of said pipe to provide a protective means for said pipeduring the handling and storage thereof.
 3. The method of making atubular pipe as in claim 2 wherein said annular ring is removed fromsaId groove in said pipe prior to assembly of said pipe to another pipeto permit an O-ring to be installed in said groove.